Magento 2 contact form post action 302 error?

Whenever I submit my contact form and check with the Chrome dev tools, I am getting a 302 not found error for contact/index/post/ an empyt error message on the frontend and a redirect to the contact form. Nothing is in the logs.

The form key is also there:

<input name="form_key" type="hidden" value="G8qe2gaMu5HWXclx" />

I checked if the controller is there and it seems that it is, its in vendor/magento/module-contact/Controller/Index/Post.php and the content also looks ok.

Strange thing is, whenever I add something to test if the code really goes there, it seems that it is not coming to the excecute method.